SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2026-34576

Prior to version 2.21.3, the POST /public/v1/upload-from-url endpoint accepts a user-supplied URL and fetches it server-side using axios.get() with no SSRF protections.

HIGH 8.3EPSS 0.27%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.27%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Postiz is an AI social media scheduling tool. Prior to version 2.21.3, the POST /public/v1/upload-from-url endpoint accepts a user-supplied URL and fetches it server-side using axios.get() with no SSRF protections. The only validation is a file extension check (.png, .jpg, etc.) which is trivially bypassed by appending an image extension to any URL path. An authenticated API user can fetch internal network resources, cloud instance metadata, and other internal services, with the response data uploaded to storage and returned to the attacker. This issue has been patched in version 2.21.3.

CVSS 4.0
8.3 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS
0.27% probability · 19th percentile
CISA KEV
Not listed
Weakness
CWE-918
Affected
gitroom/postiz
Source
security-advisories@github.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.